WO2024011439A1

WO2024011439A1 - Semiconductor packaged device and method for manufacturing the same

Info

Publication number: WO2024011439A1
Application number: PCT/CN2022/105351
Authority: WO
Inventors: Lei Zhang; Bangxing CHEN
Original assignee: Innoscience (Zhuhai) Technology Co., Ltd.
Priority date: 2022-07-13
Filing date: 2022-07-13
Publication date: 2024-01-18

Abstract

A semiconductor packaged device includes a semiconductor die, a conductive clip, and an encapsulant. The conductive clip is disposed over a back surface of the semiconductor die and thermally coupled to the semiconductor die. The conductive clip spans across the back surface of the semiconductor die and extends downward to a first position that is out of the semiconductor die and lower than an active surface of the semiconductor die facing away the conductive clip. The encapsulant encapsulates the semiconductor die and the conductive clip.

Description

SEMICONDUCTOR PACKAGED DEVICE AND METHOD FOR MANUFACTURING THE SAME

Inventors: Lei ZHANG; Bangxing CHEN

Field of the Disclosure:

The present disclosure generally relates to a nitride-based semiconductor packaged device. More specifically, the present disclosure relates to a nitride-based semiconductor packaged device having a dual-side cooled nitride-based semiconductor die.

Background of the Disclosure:

In recent years, intense research on high-electron-mobility transistors (HEMTs) has been prevalent, particularly for high power switching and high frequency applications. III-nitride-based HEMTs utilize a heterojunction interface between two materials with different bandgaps to form a quantum well-like structure, which accommodates a two-dimensional electron gas (2DEG) region, satisfying demands of high power/frequency devices. In addition to HEMTs, examples of devices having heterostructures further include heterojunction bipolar transistors (HBT) , heterojunction field effect transistor (HFET) , and modulation-doped FETs (MODFET) .

Summary of the Disclosure:

In accordance with one aspect of the present disclosure, a semiconductor packaging device is provided. The semiconductor packaged device includes a semiconductor die, a conductive clip, and an encapsulant. The conductive clip is disposed over a back surface of the semiconductor die and thermally coupled to the semiconductor die. The conductive clip spans across the back surface of the semiconductor die and extends downward to a first position that is out of the semiconductor die and lower than an active surface of the semiconductor die facing away the conductive clip. The encapsulant encapsulates the semiconductor die and the conductive clip.

In accordance with one aspect of the present disclosure, a method for manufacturing a semiconductor packaged device is provided. The method includes steps as follows. A semiconductor die is mounted on a substrate, such that an active surface of the semiconductor die faces the substrate. A conductive clip is formed over a back surface of the semiconductor die opposite to the active surface, such that the conductive clip is formed to span across the back surface of the semiconductor die and extend downward to a first position that is out of the semiconductor die and lower than the active surface of the semiconductor die. The semiconductor die and the conductive clip are encapsulated.

In accordance with one aspect of the present disclosure, a semiconductor packaged device is provided. The semiconductor packaged device includes a semiconductor die, a conductive clip, and an encapsulant. The semiconductor die has an active surface and a back surface opposite to each other. The conductive clip is disposed over the back surface of the semiconductor die and thermally coupled to the semiconductor die. The conductive clip includes a main body portion and a downward-extending portion connected to the main body portion. The main body portion spans across the back surface of the semiconductor die. The downward-extending portion extends from a first position directly above the back surface to a second position lower the active surface and has at least one protruding portion located therebetween. The encapsulant encapsulates the semiconductor die and the conductive clip.

By the above configuration, in the present disclosure, a conducting clip is disposed over a back surface of the semiconductor die and is thermally coupled thereto. On the other hand, at least one of heat dissipation pins can be disposed at an active surface of the semiconductor die and thermally coupled thereto. Then, the semiconductor die is achieved to be dual-side cooled. Thus, the semiconductor packaged device can have a good heat dissipation ability.

Brief Description of the Drawings:

Aspects of the present disclosure are readily understood from the following detailed description when read with the accompanying figures. It should be noted that various features may not be drawn to scale. That is, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion. Embodiments of the present disclosure are described in more detail hereinafter with reference to the drawings, in which:

FIG. 1A is a bottom view of a semiconductor packaged device according to some embodiments of the present disclosure;

FIG. 1B is a vertical cross-sectional view of the semiconductor packaged device taken along a line A-A’ in FIG. 1A;

FIG. 1C is a vertical cross-sectional view of a GaN-based transistor in the semiconductor packaged device of the FIG. 1A;

FIG. 2A, FIG. 2B, FIG. 2C, and FIG. 2D show different stages of a method for manufacturing a semiconductor packaged device according to some embodiments of the present disclosure;

FIG. 3 is a bottom view of a semiconductor packaged device according to some embodiments of the present disclosure;

FIG. 4 is a vertical cross-sectional view of a semiconductor packaged device according to some embodiments of the present disclosure;

FIG. 5 is a vertical cross-sectional view of the semiconductor packaged device according to some embodiments of the present disclosure;

FIG. 6 is a vertical cross-sectional view of a semiconductor packaged device according to some embodiments of the present disclosure;

FIG. 7 is a vertical cross-sectional view of a semiconductor packaged device according to some embodiments of the present disclosure; and

FIG. 8 is a vertical cross-sectional view of a semiconductor packaged device according to some embodiments of the present disclosure.

Detailed Description:

Common reference numerals are used throughout the drawings and the detailed description to indicate the same or similar components. Embodiments of the present disclosure will be readily understood from the following detailed description taken in conjunction with the accompanying drawings.

Spatial descriptions, such as "on, " "above, " "below, " "up, " "left, " "right, " "down, " "top, " "bottom, " "vertical, " "horizontal, " "side, " "higher, " "lower, " "upper, " "over, " "under, " and so forth, are specified with respect to a certain component or group of components, or a certain plane of a component or group of components, for the orientation of the component (s) as shown in the associated figure. It should be understood that the spatial descriptions used herein are for purposes of illustration only, and that practical implementations of the structures described herein can be spatially arranged in any orientation or manner, provided that the merits of embodiments of this disclosure are not deviated from by such arrangement.

Further, it is noted that the actual shapes of the various structures depicted as approximately rectangular may, in actual device, be curved, have rounded edges, have somewhat uneven thicknesses, etc. due to device fabrication conditions. The straight lines and right angles are used solely for convenience of representation of layers and features.

In the following description, semiconductor packaged devices/dies/packages, methods for manufacturing the same, and the likes are set forth as preferred examples. It will be apparent to those skilled in the art that modifications, including additions and/or substitutions may be made without departing from the scope and spirit of the present disclosure. Specific details may be omitted so as not to obscure the present disclosure; however, the disclosure is written to enable one skilled in the art to practice the teachings herein without undue experimentation.

As the operating speed of the transistor increases, so does heat generation. Excessive heat may accumulate in the semiconductor packaged device, resulting in malfunction of the semiconductor packaged device. Furthermore, the quality of an encapsulant of the semiconductor packaged device will worsen due to excessive heat. The reliability and performance of the semiconductor packaged device is decreased as the temperature increases.

Generally speaking, a semiconductor die can be flip-chip mounted to a printed circuit board (PCB) through heating dissipating pins therebetween. Heat dissipation performance of the semiconductor die is mainly dominated by the size of the heating dissipating pins, and the size and location of the heating dissipating pins are limited by the size and the location of the semiconductor die. Moreover, the demands for miniaturization of the electronic device require an active surface of the semiconductor die more smaller than the past model, and thus the heat dissipation performance of the semiconductor die would be limited.

At least for avoiding the aforesaid issues, the present disclosure provides a novel structure/arrangement for the semiconductor packaged device.

FIG. 1A is a bottom view of a semiconductor packaged device according to some embodiments of the present disclosure. FIG. 1B is a vertical cross-sectional view of the semiconductor packaged device taken along a line A-A’ in FIG. 1A.

Referring to FIGS. 1A and 1B, the semiconductor packaged device 1A includes a semiconductor die 10, a bonding layer 12A, a conductive clip 20A (or contact clip) , a substrate 30, a plurality of conductive bumps 40 (i.e., solder bumps) , and an encapsulant 50.

The semiconductor packaged device 1A can be arranged in a space defined by directions D1, D2 and D3. The directions D1, D2, and D3 are labeled in the FIGS. 1A and 1B. The directions D1, D2 and D3 are different from each other. In some embodiments, the directions D1, D2 and D3 are perpendicular to each other.

The semiconductor die 10 has an active surface AS (i.e., a top surface) , a back surface BS (i.e., a bottom surface/non-active surface) , and a pair of side surfaces SS1, SS2. The active surface AS is opposite to the back surface BS. The side surface SS1 is opposite to the side surface SS2. Each of the side surfaces SS1, SS2 connects the active surface AS to the back surface BS. In the embodiment, the semiconductor die 10 can have a rectangular profile. In some embodiments, the semiconductor die 10 can have a trapezoid profile.

The active surface AS of the semiconductor die 10 can contain analog or digital circuits implemented as active devices, passive devices, conductive layers, and dielectric layers formed within the die and electrically interconnected according to the electrical design and function of the die. For example, the circuit may include one or more transistors, diodes, or other circuit elements formed within active surface AS to implement analog circuits or digital circuits. As such, the active surface AS is the main heating surface of the semiconductor die 10. During the operation of the semiconductor packaged device 1A, the semiconductor die 10 will generate heat in the semiconductor packaged device 1A. Thus, the semiconductor die 10 act as a main heat source/heat-generating electronic component, which means that the highest temperature in the semiconductor packaged device 1A occurs in a region occupied by the semiconductor die 10.

In some embodiments, the semiconductor die 10 can include a transistor. The transistor can be formed adjacent to the active surface AS of the semiconductor die 10. In some embodiments, the transistor is a GaN-based transistor. FIG. 1C is a vertical cross-sectional view of a GaN-based transistor 10 in the semiconductor packaged device 1A of the FIG. 1A. The transistor 10 includes a substrate 102, a nitride-based semiconductor layer 103, a nitride-based semiconductor layer 104,

electrodes

105, 106, a doped nitride-based semiconductor layer 107, and a gate electrode 108. The detailed configuration of the transistor 1A is fully depicted as shown in FIG. 1C.

Referring to FIG. 1C, the substrate 102 may be a semiconductor substrate. The exemplary materials of the substrate 102 can include, for example but are not limited to, Si, SiGe, SiC, gallium arsenide, p-doped Si, n-doped Si, sapphire, semiconductor on insulator, such as silicon on insulator (SOI) , or other suitable substrate materials. In some embodiments, the substrate 102 can include, for example, but is not limited to, group III elements, group IV elements, group V elements, or combinations thereof (e.g., III-V compounds) . In other embodiments, the substrate 102 can include, for example but is not limited to, one or more other features, such as a doped region, a buried layer, an epitaxial (epi) layer, or combinations thereof.

In some embodiments, the transistor can include a buffer layer (not shown) . The buffer layer (not shown) can be disposed on/over/above the substrate 102. The buffer layer can be disposed between the substrate 102 and the nitride-based semiconductor layer 103. The buffer layer can be configured to reduce lattice and thermal mismatches between the substrate 102 and the nitride-based semiconductor layer 103, thereby curing defects due to the mismatches/difference. The buffer layer may include a III-V compound. The III-V compound can include, for example but are not limited to, aluminum, gallium, indium, nitrogen, or combinations thereof. Accordingly, the exemplary materials of the buffer layer can further include, for example but are not limited to, GaN, AlN, AlGaN, InAlGaN, or combinations thereof.

In some embodiments, the transistor may further include a nucleation layer (not shown) . The nucleation layer may be formed between the substrate 102 and the buffer layer. The nucleation layer can be configured to provide a transition to accommodate a mismatch/difference between the substrate 102 and a III-nitride layer of the buffer layer. The exemplary material of the nucleation layer can include, for example but is not limited to AlN or any of its alloys.

The nitride-based semiconductor layer 103 is disposed on/over/above the substrate 102. The nitride-based semiconductor layer 104 is disposed on/over/above the nitride-based semiconductor layer 103. The exemplary materials of the nitride-based semiconductor layer 103 can include, for example but are not limited to, nitrides or group III-V compounds, such as GaN, AlN, InN, In _xAl _yGa _(1–x–y) N where x+y ≤ 1, Al _xGa _(1–x) N where x ≤ 1. The exemplary materials of the nitride-based semiconductor layer 104 can include, for example but are not limited to, nitrides or group III-V compounds, such as GaN, AlN, InN, In _xAl _yGa _(1–x–y) N where x+y ≤ 1, Al _yGa _(1–y) N where y ≤ 1.

The exemplary materials of the nitride-based semiconductor layers 103 and 104 are selected such that the nitride-based semiconductor layer 104 has a bandgap (i.e., forbidden band width) greater than a bandgap of the nitride-based semiconductor layer 103, which causes electron affinities thereof different from each other and forms a heterojunction therebetween. For example, when the nitride-based semiconductor layer 103 is an undoped GaN layer having a bandgap of approximately 3.4 eV, the nitride-based semiconductor layer 104 can be selected as an AlGaN layer having bandgap of approximately 4.0 eV. As such, the nitride-based semiconductor layers 103 and 104 can serve as a channel layer and a barrier layer, respectively. A triangular well potential is generated at a bonded interface between the channel and barrier layers, so that electrons accumulate in the triangular well, thereby generating a two-dimensional electron gas (2DEG) region adjacent to the heterojunction. Accordingly, the transistor is available to include at least one GaN-based high-electron-mobility transistor (HEMT) .

The

electrodes

105 and 106 are disposed on/over/above the nitride-based semiconductor layer 104. The

electrodes

105 and 106 can make contact with the nitride-based semiconductor layer 104. In some embodiments, the electrode 105 can serve as a source electrode. In some embodiments, the electrode 105 can serve as a drain electrode. In some embodiments, the electrode 106 can serve as a source electrode. In some embodiments, the electrode 106 can serve as a drain electrode. The role of the

electrodes

105 and 106 depends on the device design.

In some embodiments, the

electrodes

105 and 106 can include, for example but are not limited to, metals, alloys, doped semiconductor materials (such as doped crystalline silicon) , compounds such as silicides and nitrides, other conductor materials, or combinations thereof. The exemplary materials of the

electrodes

105 and 106 can include, for example but are not limited to, Ti, AlSi, TiN, or combinations thereof. Each of the electrodes 1024 and 1025 may be a single layer, or plural layers of the same or different composition. The

electrodes

105 and 106 form ohmic contacts with the nitride-based semiconductor layer 104. Furthermore, the ohmic contacts can be achieved by applying Ti, Al, or other suitable materials to the

electrodes

105 and 106.

In some embodiments, each of the

electrodes

105 and 106 is formed by at least one conformal layer and a conductive filling. The conformal layer can wrap the conductive filling. The exemplary materials of the conformal layer can include, for example but are not limited to, Ti, Ta, TiN, Al, Au, AlSi, Ni, Pt, or combinations thereof. The exemplary materials of the conductive filling can include, for example but are not limited to, AlSi, AlCu, or combinations thereof.

The doped nitride-based semiconductor layer 107 is disposed on/above the nitride-based semiconductor layer 104. The gate electrode 108 is disposed/stacked on the doped nitride-based semiconductor layer 107. The doped nitride-based semiconductor layer 107 and the gate electrode 1027 are disposed between the

electrodes

105 and 106.

A width of the doped nitride-based semiconductor layer 107 is greater than that of the gate electrode 108. In some embodiments, a width of the doped nitride-based semiconductor layer 107 is substantially the same as a width of the gate electrode 108. The relationship of the widths of the doped nitride-based semiconductor layer 107 and the gate electrode 108 can depend on the device design.

In the exemplary illustration of FIG. 1C, the transistor is an enhancement mode device, which is in a normally-off state when the gate electrode 108 is at approximately zero bias. Specifically, the doped nitride-based semiconductor layer 107 may create at least one p-n junction with the nitride-based semiconductor layer 104 to deplete the 2DEG region, such that at least one zone of the 2DEG region corresponding to a position below the corresponding the gate electrode 108 has different characteristics (e.g., different electron concentrations) than the remain of the 2DEG region and thus is blocked.

Due to such mechanism, the transistor has a normally-off characteristic. In other words, when no voltage is applied to the gate electrode 108 or a voltage applied to the gate electrode 108 is less than a threshold voltage (i.e., a minimum voltage required to form an inversion layer below the gate electrode 108) , the zone of the 2DEG region below the gate electrode 108 is kept blocked, and thus no current flows therethrough.

In some embodiments, the doped nitride-based semiconductor layer 107 can be omitted, such that the transistor is a depletion-mode device, which means the transistor in a normally-on state at zero gate-source voltage.

The doped nitride-based semiconductor layer 107 can be a p-type doped III-V semiconductor layer. The exemplary materials of the doped nitride-based semiconductor layer 107 can include, for example but are not limited to, p-doped group III-V nitride semiconductor materials, such as p-type GaN, p-type AlGaN, p-type InN, p-type AlInN, p-type InGaN, p-type AlInGaN, or combinations thereof. In some embodiments, the p-doped materials are achieved by using a p-type impurity, such as Be, Zn, Cd, and Mg. In some embodiments, the nitride-based semiconductor layer 103 includes undoped GaN and the nitride-based semiconductor layer 104 includes AlGaN, and the doped nitride-based semiconductor layer 107 is a p-type GaN layer which can bend the underlying band structure upwards and to deplete the corresponding zone of the 2DEG region, so as to place the transistor into an off-state condition.

The exemplary materials of the gate electrode 108 may include metals or metal compounds. The gate electrode 108 may be formed as a single layer, or plural layers of the same or different compositions. The exemplary materials of the metals or metal compounds can include, for example but are not limited to, W, Au, Pd, Ti, Ta, Co, Ni, Pt, Mo, TiN, TaN, metal alloys or compounds thereof, or other metallic compounds.

At least for achieving a better heat dissipating performance, the present disclosure forms an additional thermal path. The detailed configuration would be fully described as follows.

Referring back to FIGS. 1B and 1C, the bonding layer 12A can be disposed/arranged on the back surface BS of the semiconductor die 10. The side surfaces SS1, SS2, and the active surface AS of the semiconductor die 10 are free from coverage of the bonding layer 12A. In some embodiments, the bonding layer 12A can include thermal interface material (TIM) with high thermal conductivity reduce overall thermal resistance. The exemplary materials of the bonding layer 12A can include, for example but are not limited to, metal, metal alloys or compounds thereof, or other metallic compounds.

The conductive clip 20A is disposed on/over/above the back surface BS of the semiconductor die 10. The bonding layer 12 is disposed between the back surface BS of the semiconductor die 10 and the conductive clip 12A. The back surface BS of the semiconductor die 10 faces toward (or faces up) the conductive clip 20A and the bonding layer 12, and the active surface AS of the semiconductor die 10 faces away (or face down) the conductive clip 20A.

The bonding layer 12A is inserted between the conductive clip 20A of the semiconductor die 10 at least in order to enhance the thermal coupling between them. The bonding layer 12A makes contact with the conductive clip 20A and the back surface BS of the semiconductor die 10. The conductive clip 20A is bonded to the back surface BS of the semiconductor die 10 through the bonding layer 12A. In the embodiment, the bonding layer 12A covers an entirety of the back surface BS of the semiconductor die 10. Such a configuration can make a contact area/region between the back surface BS of the semiconductor die 10 and the bonding layer 12A to be as large as possible, which is advantageous to improve heat dissipation performance. Thus, the conductive clip 20A can be well thermally coupled to the back surface BS of the semiconductor die 10 through the bonding layer 12A.

In some embodiment, the bonding layer 12A can partially covers the back surface BS of the semiconductor die 10. The present disclosure is not limited thereto.

The conductive clip 20A includes a main body portion 202A and two downward-extending portions 204A. The main body portion 202A spans across the back surface BS of the semiconductor die 10. The main body portion 202A extends horizontally/laterally over the back surface BS, such that a width of the main body portion 202A can exceed that of the back surface BS.

The two downward-extending portions 204A are located at two opposite sides of the main body portion 202A, respectively. The downward-extending portions 204A are connected to the main body portion 202A. The two downward-extending portions 204A connect two opposite edge regions of the main body portion 202A, respectively. Each of the downward-extending portions 204A extends downward from a position P2 that is out of the semiconductor die 10 and higher than the back surface BS to a position P1. Each of the downward-extending portions 204A extends downward from a position P2 that is out of the semiconductor die 10 and higher than the back surface BS to a position P1 that is out of the semiconductor die 10 and lower than the active surface AS, which means that each of the downward-extending portions 204A spans across the thickness T of the semiconductor die 10.

Each of the two downward-extending portions 204A of the conductive clip 20A extends downward in a substantially vertical manner. Each of the two downward-extending portions 204A can have the same extending length. Therefore, the conductive clip 20A can have a substantial symmetry profile.

The extending length of each of the downward-extending portions 204A is greater than a thickness T of the semiconductor die 10, in which the thickness T is defined by the active and back surfaces AS, BS. The two downward-extending portions 204A cover two opposite side surfaces SS1, SS2 of the semiconductor die 10, respectively. The main body portion 204A and the downward-extending portions 204A can collectively forms a cavity to receive the semiconductor die 10. By the aforesaid configuration, the conductive clip 20A can provide a good protection to the semiconductor die 10.

In some embodiments, the bonding layer 12A can be omitted at least for reducing the manufacturing cost of the semiconductor packaged device, and the conductive clip 20A can directly make contact with the back surface BS of the semiconductor die 10.

In some embodiments, the back surface BS of the semiconductor die 10 is electrical isolation. For example, the back surface BS of the semiconductor die 10 is free from conductive pad, trace, electrode. The purpose of the connection to the conductive clip 20A from the back surface BS of the semiconductor die 10 through the bonding layer 12A is based on consideration of heat dissipation. Such the heat dissipation can be achieved by heat conduction. It is advantageous to layout of the of the main body portion 202A of the conductive clip 20A. The profile of the main body portion 202A of the conductive clip 20A is flexible because consideration to circuit layout is omitted.

The substrate 30A can be disposed directly under the semiconductor die 10. The substrate 30A has a die attached region DR and an non-die attached region NDR. According to electrical circuits design, the semiconductor die 10 is preset to be disposed (or arranged) on/over/above the die attached region DR of the substrate 30A. The non-die attached region NDR is adjacent to the die attach region DR. Generally speaking, the non-die attached region NDR has a much greater area than that of the die attached region DR. Referring to FIGS. 1A and 1B, the substrate 30A includes at least one heat-dissipation pins 302, a heat sink 304A, a thermal conductive pad 306, a heat sink 308A, and a plurality of terminal pads TP.

In the present disclosure, the phrase “heat sink” commonly refers to a passive heat exchanger that transfers heat generated by an electronic component/element (i.e., the semiconductor die 10) to a fluid medium (i.e., air or other suitable liquid coolant) . In the device, the heat sink usually owns temperature lower than that of the electronic component/element, such that a temperature gradient therebetween can be created, thereby transferring the heat from the electronic component/element to the heat sink.

With respect to the die attached region DR, the heat-dissipation pins 302 and the heat sink 308A are disposed therein. The heat-dissipation pins 302 are disposed on/over/above separated portions of the heat sink 308A. The heat-dissipation pins 302 make contact with portions of the heat sink 308A. Prior to mount the semiconductor die 10 on the die attached region DR, the conductive bumps 40 can be disposed (or implanted) on/over/above the heat-dissipation pins 302, respectively. The semiconductor die 10 is directly disposed over the die attach region DR of the substrate 30A. The active surface AS of the semiconductor die 10 faces down (or faces toward) the conductive bumps 40, the heat-dissipation pins 302, and the heat sink 308A. The active surface AS of the semiconductor die 10 can make contact with the conductive bumps 40, such that the semiconductor die 10 can be thermally coupled to the heat sink 308A through the conductive bumps 40. That is to say, the semiconductor die 10 is flip-chip mounted on the die attached region DR. Therefore, a thermal conductive path TP1, which is from the active surface AS of the semiconductor die 10, the conductive bump 40, the heat-dissipation pin 302 to the heat sink 308A, can be formed. A portion of heat generated by the semiconductor die 10 can be transferred by the aforesaid thermal conductive path TP1.

It should be noted that a width of the heat-dissipation pin 302 is smaller than that of the semiconductor die 10 since the size of the heat-dissipation pin 302 is limited by the size of the semiconductor die 10.

With respect to the non-die attached region NDR, the thermal pads 306 and separated portions of the heat sink 304A are disposed therein. Each of the thermal conducive pad 306 is disposed on/over/above a top surface of the corresponding portion of the heat sink 304A. Each of the separated portions of the heat sink 304A can extend along the direction D3. The downward-extending portion 204A of the conductive clip 20A extends downward to non-die attached region NDR, thereby making contact with the thermal conducive pad 306. Therefore, the conductive clip 20A is thermally coupled to the heat sink 308A through the thermal conductive pad 306. Thus, another thermal conductive path TP2, which is from the back surface BS of the semiconductor die 10, the main body portion 202A, the downward-extending portion 204A, the thermal bonding layer 306, to the heat sink 304A, can be formed. A portion of heat generated by the semiconductor die 10 can be transferred by the aforesaid thermal conductive path TP2.

In some embodiments, the thermal conductive path TP1 is configured to transmit electronic signal and heat flow while the thermal conductive path TP2 is configured to transmit heat flow without electronic signal.

It should be noted that a width of the thermal conductive pad 306 in the non-die attached region NDR can be designed greater than that of the heat-dissipation pin 302 in the die attached region DR since the size of the thermal conductive pad 306 is unrestricted by the size of the semiconductor die 10. Thus, the heat dissipation ability of the semiconductor packaged device 1A can be further improved.

Moreover, at least by a configuration that the downward extending portion 204A extends to a position P1 that is out of the semiconductor die 10 and is within the non-die attached region NDR with a greater area, the location and size of the thermal conductive pad 306 can be freely designed instead of limiting by the location and area of die attached region DR. Therefore, the heat dissipating design/layout of the semiconductor packaged device 1A can be more flexible.

In the present disclosure, by configuration of the conductive bumps 40, heat-dissipating pins 302 and the heat sink 308, a thermal conductive path TP1 is thus formed directly under the active surface of the semiconductor die 10. By configuration of the conductive clip 20A, the thermal conductive pad 306, and the heat sink 304, an additional thermal conductive path TP2 is thus formed. The semiconductor die 10 is achieved to be dual-side cooled by aforesaid configuration. Thus, heat dissipating performance of the semiconductor packaged device 1A can be greatly promoted.

The encapsulant 50 encapsulates the semiconductor die 10 and the conductive clip 20A, and the substrate 30 for environmental protection by preventing moisture and particles from entering the semiconductor packaged device 1A. At least a portion of the encapsulant 50 is located between the conductive clip 20A and the semiconductor die 10 (or the bonding layer 12A) . The conductive clip 20A is spaced apart from the semiconductor die 10 by the encapsulant 50.

Referring to FIG. 1A, the terminal pads TP are arranged at edges of the semiconductor packaged device 1A. In some embodiments, at least one of the external electronic devices can be electrically coupled/connected to the terminals pads PD to send at least one signals to the semiconductor packaged device 1A, and vice versa. The exemplary materials of the terminal pads TP can include, for example but not limited to, conductive materials, such as metals or alloys.

The exemplary materials of the heat-dissipation pins 302 and the conductive clip 20A have a favorable heat conductivity such as metal materials. The metal materials can include, for example but are not limited to, Ag, Cu, Au, Al, Mo, W, Zn or metal alloy.

The exemplary materials of the conductive bumps 40 can include, for example but are not limited to, Al, Cu, Sn, Ni, Au, Ag or a combination thereof.

The exemplary materials of the encapsulant 50 can include, for example but are not limited to, polymer composite material, such as epoxy resin with filler, epoxy acrylate with filler, or polymer with proper filler.

Different stages of a method for manufacturing the semiconductor packaged device 1A are shown in FIG. 2A, FIG. 2B, FIG. 2C, and FIG 2D described below. In the following, deposition techniques can include, for example but are not limited to, atomic layer deposition (ALD) , physical vapor deposition (PVD) , chemical vapor deposition (CVD) , metal organic CVD (MOCVD) , plasma enhanced CVD (PECVD) , low-pressure CVD (LPCVD) , plasma-assisted vapor deposition, epitaxial growth, or other suitable processes.

Referring to FIG. 2A, a substrate 30A is provided. The conductive bumps 40 are formed/implanted/disposed/arranged on the heat dissipation pins 302 in the die attached region DR.

Referring to FIG. 2B, the semiconductor die 10 is flip-chip mounted on the die attached region DR of the substrate 30A through the conductive bumps 40, such that an active surface AS of the semiconductor die 10 faces down (or faces toward) the substrate 30.

Referring to FIG. 2C, a bonding layer 12A is formed on the back surface BS of the semiconductor die 10.

Referring to FIG. 2D, a conductive clip 20A is formed on/over/above the back surface BS of the semiconductor die 10 to span across the back surface BS of the semiconductor die 10. The formed conductive clip 20A extends downward from a position P2 that is out of the semiconductor die 10 and higher than the back surface BS of the semiconductor die 10 to a position P1 that is out of the semiconductor die 10 and lower than the active surface AS of the semiconductor die 10. Thereafter, the semiconductor die 10, the conductive clip 20A, and the substrate 30A are encapsulated by an encapsulant 50, and the semiconductor packaged device 1A in the FIG. 1A is obtained.

FIG. 3 is a bottom view of a semiconductor packaged device 1B according to some embodiments of the present disclosure. The semiconductor packaged device 1B is similar to the semiconductor packaged device 1A as described and illustrated with reference to FIG. 1A, except that each of the portions of the heat sink 308B in the die-attached region DR can extend along the direction D3, such that two opposite edges of each of the portions of the heat sink 308B can align with two opposite edges (i.e., upper and lower edges) of the semiconductor packaged device 1B, respectively. Therefore, the heating dissipating surface of the heat sink 308B can be increased, thereby enhancing the heat dissipating performance of the semiconductor packaged device 1B.

FIG. 4 is a vertical cross-sectional view of a semiconductor packaged device 1C. The semiconductor packaged device 1C is similar to the semiconductor packaged device 1A as described and illustrated with reference to FIG. 1B, except that the conductive clip 20C can have an asymmetry profile. Specifically, the conductive clip 20C includes only one downward-extending portion 204C connecting to an edge region of the main body portion 202C. The profile/shape of the conductive clip 20C is conducive to enhance the flexibility of the layout of the semiconductor packaged device 1C.

FIG. 5 is a vertical cross-sectional view of a semiconductor packaged device 1D. The semiconductor packaged device 1D is similar to the semiconductor packaged device 1A as described and illustrated with reference to FIG. 1B, except that conductive clip 20D can have an asymmetry profile. Specifically, one of the downward-extending portion 204D2 has a thicker thickness than the downward-extending portion 204D1, such that the conductive clip 20D can have an asymmetry profile. The asymmetry profile is based on consideration of GaN-based transistors. The GaN-based transistors may have an asymmetry configuration, so as to match high voltage device requirement.

FIG. 6 is a vertical cross-sectional view of a semiconductor packaged device 1E. The semiconductor packaged device 1E is similar to the semiconductor packaged device 1A as described and illustrated with reference to FIG. 1B, except that each of the downward-extending portions 204E extends downward in an inclined manner. Thus, the heating dissipating area of the conductive clip 20E can be increased, thereby enhancing the heat dissipating performance of the semiconductor packaged device 1E.

In some embodiments, one of the downward-extending portions 204E can having an extending length different from that of the other one of downward-extending portions 204E. In some embodiments, an including angle between the one of the downward-extending portions and the corresponding portion of the heat sink 304E can be different from that of the other one of the downward-extending portions and the corresponding portion of the heat sink 304E. Such configurations can provide more design flexibility to the semiconductor packaged device 1E.

FIG. 7 is a vertical cross-sectional view of a semiconductor packaged device 1F. The semiconductor packaged device 1F is similar to the semiconductor packaged device 1A as described and illustrated with reference to FIG. 1B, except that the downward-extending portion of the conductive clip 20F can have at least one protruding portion PP located between the positions P1 and P2 in which the protruding portion PP protrudes from a direction away from the semiconductor die 10. Thus, the heating dissipating area of the conductive clip 20F can be increased, thereby enhancing the heat dissipating performance of the semiconductor packaged device 1F.

In some embodiments, the conductive clip can have a recessed portion recessed toward the semiconductor die 10. The disclosure is not limited thereto.

FIG. 8 is a vertical cross-sectional view of a semiconductor packaged device 1G. The semiconductor packaged device 1G is similar to the semiconductor packaged device 1A as described and illustrated with reference to FIG. 1B, except that the bonding layer 12G covers the side surfaces SS1, SS2 and the back surface BS of the semiconductor die 10, and an active surface AS of the semiconductor die 10 is free from coverage of the bonding layer 12G. The main body portion 202G of the conductive clip 20G extends along the direction D1 and then turns to extend along an anti-direction of the direction D2, such that the main body partition 202G can cap/make contact with the bonding layer 12G. By such a configuration, the thermal resistance between the semiconductor die 10 and the conductive clip can be further reduced, and thus the heat dissipating performance of the semiconductor packaged device 1G can be further improved.

Furthermore, since GaN-based transistor/die is formed from epitaxial growth, external bending to the GaN-based transistor/die will result in crack once the GaN-based transistor/die is mounted unstably. Because the conductive clip 20G can fix the semiconductor die 10 at least along directions D1 and D2, bending resulting from uneven external force is avoided so as to protect epitaxial layers of the semiconductor die 10 from cracking.

Based on above, in the present disclosure, a conducting clip is disposed over a back surface of the semiconductor die and is thermally coupled thereto through a TIM material. Furthermore, the conducting clip can extend to a position within an non-die attached region having a greater area; and therefore, the heat dissipating design/layout of the semiconductor packaged device can be more flexible. In addition, the conducting clip can have some structural features (such as protruding portion) to enlarge the heat dissipating area thereof, thereby improving the heat dissipating performance of the semiconductor packaged device. Therefore, the semiconductor packaged device can have good performance and reliability.

The embodiments were chosen and described in order to best explain the principles of the disclosure and its practical application, thereby enabling others skilled in the art to understand the disclosure for various embodiments and with various modifications that are suited to the particular use contemplated.

As used herein and not otherwise defined, the terms "substantially, " "substantial, " "approximately" and "about" are used to describe and account for small variations. When used in conjunction with an event or circumstance, the terms can encompass instances in which the event or circumstance occurs precisely as well as instances in which the event or circumstance occurs to a close approximation. For example, when used in conjunction with a numerical value, the terms can encompass a range of variation of less than or equal to ±10%of that numerical value, such as less than or equal to ±5%, less than or equal to ±4%, less than or equal to ±3%, less than or equal to ±2%, less than or equal to ±1%, less than or equal to ±0.5%, less than or equal to ±0.1%, or less than or equal to ±0.05%. The term “substantially coplanar” can refer to two surfaces within micrometers of lying along a same plane, such as within 40 μm, within 30 μm, within 20 μm, within 10 μm, or within 1 μm of lying along the same plane.

As used herein, the singular terms “a, ” “an, ” and “the” may include plural referents unless the context clearly dictates otherwise. In the description of some embodiments, a component provided “on” or “over” another component can encompass cases where the former component is directly on (e.g., in physical contact with) the latter component, as well as cases where one or more intervening components are located between the former component and the latter component.

While the present disclosure has been described and illustrated with reference to specific embodiments thereof, these descriptions and illustrations are not limiting. It should be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the true spirit and scope of the present disclosure as defined by the appended claims. The illustrations may not necessarily be drawn to scale. There may be distinctions between the artistic renditions in the present disclosure and the actual apparatus due to manufacturing processes and tolerances. Further, it is understood that actual devices and layers may deviate from the rectangular layer depictions of the FIGS. and may include angles surfaces or edges, rounded corners, etc. due to manufacturing processes such as conformal deposition, etching, etc. There may be other embodiments of the present disclosure which are not specifically illustrated. The specification and the drawings are to be regarded as illustrative rather than restrictive. Modifications may be made to adapt a particular situation, material, composition of matter, method, or process to the objective, spirit and scope of the present disclosure. All such modifications are intended to be within the scope of the claims appended hereto. While the methods disclosed herein have been described with reference to particular operations performed in a particular order, it will be understood that these operations may be combined, sub-divided, or re-ordered to form an equivalent method without departing from the teachings of the present disclosure. Accordingly, unless specifically indicated herein, the order and grouping of the operations are not limitations.

Claims

A semiconductor packaged device, comprising:

a semiconductor die;

a conductive clip disposed over a back surface of the semiconductor die and thermally coupled to the semiconductor die, wherein the conductive clip spans across the back surface of the semiconductor die and extends downward to a first position that is out of the semiconductor die and lower than an active surface of the semiconductor die facing away the conductive clip; and

an encapsulant encapsulating the semiconductor die and the conductive clip.
The semiconductor packaged device of claim 1, wherein the conductive clip further comprises a main body portion spanning across the back surface of the semiconductor die and at least one downward-extending portion connected to the main body portion, wherein an extending length of the downward-extending portion is greater than a thickness of the semiconductor die.
The semiconductor packaged device of claim 2, wherein the downward-extending portion of the conductive clip extends downward from a second position to the first position, wherein the second position is out of the semiconductor die and higher than the back surface of the semiconductor die.
The semiconductor packaged device of claim 1, wherein the conductive clip extends downward in a substantially vertical manner.
The semiconductor packaged device of claim 1, wherein the conductive clip extends downward in an inclined manner.
The semiconductor packaged device of claim 1, wherein the conductive clip comprises only one downward-extending portion connecting to an edge region of the main body portion, wherein the downward-extending portion covers a side surface of the semiconductor die.
The semiconductor packaged device of claim 1, wherein the conductive clip comprises at least two downward-extending portions connecting two opposite edge regions of the main body portion, wherein the two downward-extending portions cover two opposite side surfaces of the semiconductor die, respectively.
The semiconductor packaged device of claim 1, further comprising a substrate having a die attach region and a non-die attach region adjacent to the die attach region, wherein the semiconductor die is directly disposed over the die attach region of the substrate, and the conductive clip extends downward to the non-die attach region of the substrate.
The semiconductor packaged device of claim 8, wherein the substrate further comprises at least one heat-dissipation pin disposed in the die attach region and facing toward the active surface of the semiconductor die, wherein the semiconductor die is thermally coupled to the heat-dissipation pin.
The semiconductor packaged device of claim 9, wherein a width of the heat-dissipation pin is smaller than that of the semiconductor die.
The semiconductor packaged device of claim 9, further comprising a plurality of conductive bumps between the active surface of the semiconductor die and the heat-dissipation pins, wherein the semiconductor die is thermally coupled to the heat-dissipation pins through the conductive bumps.
The semiconductor packaged device of claim 9, wherein the substrate further comprises a heat sink and a thermal conductive pad disposed in the non-die attach region, wherein the conductive clip is thermally coupled to the heat sink through the thermal conductive pad that has a width greater than that of the heat-dissipation pin.
The semiconductor packaged device of claim 1, wherein at least one portion of the encapsulant is located between the conductive clip and the semiconductor die.
The semiconductor packaged device of claim 1, further comprising a bonding layer disposed between the back surface of the semiconductor die and the conductive clip, wherein the conductive clip is thermally coupled to the semiconductor die through the bonding layer.
The semiconductor packaged device of claim 14, wherein the bonding layer makes contact with an entirety of the back surface of the semiconductor die.
A method for manufacturing a semiconductor packaged device, comprising:

mounting a semiconductor die on a substrate, such that an active surface of the semiconductor die faces the substrate;

forming a conductive clip over a back surface of the semiconductor die opposite to the active surface, such that the conductive clip is formed to span across the back surface of the semiconductor die and extend downward to a first position that is out of the semiconductor die and lower than the active surface of the semiconductor die; and

encapsulating the semiconductor die and the conductive clip.
The method of claim 16, further comprising:

forming a plurality of conductive bumps in a die attach region of the substrate prior to the step of mounting the semiconductor die on the substrate.
The method of claim 17, wherein the semiconductor die is mounted on the die attach region of the substrate through the conductive bumps.
The method of claim 16, further comprising:

forming a bonding layer on the back surface of the semiconductor die prior the step of forming the conductive clip.
The method of claim 19, wherein the conductive clip is bonded to the back surface of the semiconductor die through the bonding layer.
A semiconductor packaged device, comprising:

a semiconductor die having an active surface and a back surface opposite to each other;

a conductive clip disposed over the back surface of the semiconductor die and thermally coupled to the semiconductor die, wherein the conductive clip comprises a main body portion and a downward-extending portion connected to the main body portion, and the main body portion spans across the back surface of the semiconductor die, wherein the downward-extending portion extends from a position directly above the back surface to another position lower the active surface and has at least one protruding portion located therebetween; and

an encapsulant encapsulating the semiconductor die and the conductive clip.
The semiconductor packaged device of claim 21, wherein the main body portion and the downward-extending portion of the conductive clip forms a cavity to receive the semiconductor die.
The semiconductor packaged device of claim 21, wherein the protruding portion protrudes from a direction away from the semiconductor die.
The semiconductor packaged device of claim 21, wherein the conductive clip is spaced apart from the semiconductor die by the encapsulant.
The semiconductor packaged device of claim 21, wherein a width of the main body portion is greater than that of the semiconductor die.